Next: AST_TUNE - Set or get an AST global tuning parameter
Up: AST Routine Descriptions
Previous: AST_TRANMAP - Create a TranMap
AST_TRANN
-
Transform N-dimensional coordinates
- Description:
- This routine applies a Mapping to transform the coordinates of
a set of points in an arbitrary number of dimensions. It is the
appropriate routine to use if the coordinates are not purely 1-
or 2-dimensional and are stored in a single array (which they
need not fill completely).
- Invocation:
- CALL AST_TRANN( THIS, NPOINT,
NCOORD_IN, INDIM, IN,
FORWARD, NCOORD_OUT, OUTDIM, OUT, STATUS )
- Arguments:
-
THIS = INTEGER (Given)
-
Pointer to the Mapping to be applied.
-
NPOINT = INTEGER (Given)
-
The number of points to be transformed.
-
NCOORD_IN = INTEGER (Given)
-
The number of coordinates being supplied for each input point
(i.e. the number of dimensions of the space in which the
input points reside).
-
INDIM = INTEGER (Given)
-
The number of elements along the first dimension of the IN
array (which contains the input coordinates). This value is
required so that the coordinate values can be correctly
located if they do not entirely fill this array. The value
given should not be less than NPOINT.
-
IN( INDIM, NCOORD_IN ) = DOUBLE PRECISION (Given)
-
An array containing the coordinates of the input
(untransformed) points. These should be stored such that the
value of coordinate number COORD for input point number POINT
is found in element IN(POINT,COORD).
-
FORWARD = LOGICAL (Given)
-
A .TRUE. value indicates that the Mapping's forward
coordinate transformation is to be applied, while a .FALSE.
value indicates that the inverse transformation should be
used.
-
NCOORD_OUT = INTEGER (Given)
-
The number of coordinates being generated by the Mapping for
each output point (i.e. the number of dimensions of the
space in which the output points reside). This need not be
the same as NCOORD_IN.
-
OUTDIM = INTEGER (Given)
-
The number of elements along the first dimension of the OUT
array (which will contain the output coordinates). This value
is required so that the coordinate values can be correctly
located if they will not entirely fill this array. The value
given should not be less than NPOINT.
-
OUT( OUTDIM, NCOORD_OUT ) = DOUBLE PRECISION (Returned)
-
An array into which the coordinates of the output
(transformed) points will be written. These will be stored
such that the value of coordinate number COORD for output
point number POINT will be found in element OUT(POINT,COORD).
-
STATUS = INTEGER (Given and Returned)
-
The global status.
- Notes:
- If the forward coordinate transformation is being applied, the
Mapping supplied must have the value of NCOORD_IN for its Nin
attribute and the value of NCOORD_OUT for its Nout attribute. If
the inverse transformation is being applied, these values should
be reversed.
Next: AST_TUNE - Set or get an AST global tuning parameter
Up: AST Routine Descriptions
Previous: AST_TRANMAP - Create a TranMap
AST A Library for Handling World Coordinate Systems in Astronomy
Starlink User Note 210
R.F. Warren-Smith & D.S. Berry
24th May 2011
E-mail:ussc@star.rl.ac.uk
Copyright (C) 2009 Science \& Technology Facilities Council